A 16-year-old had his cheek fractured after being hit with a stick in a Preston park.
The teenager was in a shelter located next to tennis courts on Haslam Park in Ashton, with another 16-year-old and two 17-year-olds when they were approached by a group of lads.
One hit him before they made off with four mountain bikes.
One of the bikes – a black and grey Carrera mountain bike – has since been recovered by officers.
Three other bicycles – a dark grey Carrera Vengeance mountain bike, frame number AJ1173992, a white GT Carrera mountain bike and a black men’s bike with ‘APOLLO’ on the frame and exposed sponge on the seat – remain outstanding and police are asking the public to come forward with any information they may have about this incident and the location of the bikes.
Anyone with information can call police on 101.